The present application is based on Japanese Patent Applications Nos. 2001-16893 and 2001-77111, which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a head protection air bag device carried on a motor vehicle. More particularly, the invention relates to a head protection air bag device in which an air bag, while being folded, is stored along the upper fringe of an opening on the cabin-inside or indoor side of a vehicle, and when receiving inflation gas, the air bag develops and inflates to cover the opening.
2. Description of the Related Art
The air bag for the conventional head protection air bag device is provided with inflatable protective shielding parts which receive inflation gas and inflate to cover the openings on the cabin-inside side, as disclosed in international publication WO96/26087 and GB2314300.
The inflatable protective shielding part includes a plurality of inflation parts which are arranged in the vehicle longitudinal direction and vertically expandable so as to generate a tension in the vehicle longitudinal direction.
The air bag has a gas-inflow section through which inflation gas is introduced into the airbag, and a non gas-inflow section which rejects the inflow of the inflation gas. The non gas-inflow section includes a periphery part surrounding the gas-inflow section, and partitioning parts being vertically disposed and defining the inflation parts.
With such a structure, at the time of inflating operation, when each inflation part inflates, a distance between the partitioning parts located at the front and rear of each inflation part is reduced, and a distance between the periphery parts is also reduced. As a result, a tension having a longitudinal direction of the vehicle is generated in the inflatable protective shielding parts, so that the inflatable protective shielding parts are restrained from moving out of the car cabin at the time of restricting the passenger.
However, the conventional air bag needs improvement in the further increase of the tension generated in the lower fringe of the air bag.
In another conventional head protection air bag device, an air bag which is stored, while being folded, along the upper fringe of an opening on the cabin-inside or indoor side and on the side of seat recliners, and when receiving inflation gas, the air bag develops and inflates to cover the opening, as disclosed in Japanese Patent Publication No. 2000-335356.
In a case where the air bag is designed to have such a configuration at the completion of developing and inflating operations that its vertical dimension is large so as to cover the openings on the cabin-inside side, the following disadvantage arises. At the time of its developing/inflating operation, the air bag interferes with the seat recliner, particularly the upper end of the side surface of the seat recliner, whereby the developing/inflating operation is possibly hindered.
An object of the present invention is to provide a head protection air bag device which is able to generate high tension having a longitudinal direction of the vehicle in the lower fringe side of the air bag at the completion of developing and inflating operations of the air bag.
Another object of the present invention is to provide a head protection air bag device which enables the air bag to be developed and inflated without any interference with the seat recliners, even in such a construction that the air bag broadly covers the openings on the cabin-inside side.
According to the present invention, there is provided a first head protection air bag device having an air bag which is stored, while being folded, along the upper fringe of an opening on the cabin-inside or indoor side of a vehicle, when receiving inflation gas, the air bag developing and inflating to cover the opening,
wherein the air bag includes a gas-inflow section which inflates so as to separate a cabin-inside side wall and a cabin-outside side wall one from the other, and a non gas-inflow section which rejects inflation gas,
the gas-inflow section includes a plurality of inflatable protective shielding parts being disposed such that the inflatable protective shielding parts are longitudinally spaced from one another and cover the opening, and inflation communicating parts,
each inflatable protective shielding part includes a plurality of inflating parts which are arranged in the longitudinal direction and vertically expandable so as to generate a tension in the longitudinal direction,
the non gas-inflow section includes a periphery part surrounding the non gas-inflow section,
a plate-like portion disposed between the inflatable protective shielding parts, and partitioning parts being vertically disposed and defining the inflation parts in the inflatable protective shielding parts, the inflation communicating parts are disposed in the lower fringe side of the air bag under the plate-like portion and along the lower fringe of the air bag,
the inflatable protective shielding parts, which are adjacently located with the plate-like portion being interposed therebetween, are communicated with each other by the inflation communicating part, and
the lower ends of the inflation parts are closed at the lower-edge side parts of the periphery parts.
In the first head protection air bag device, it is preferable that one of the ends of the air bag is coupled to a body of the vehicle by coupling parts extending away from the gas-inflow section and the coupling parts are coupled to the lower-edge side part of the periphery parts at the completion of the developing and inflating operation.
In the first head protection air bag device, it is preferable that the inflatable protective shielding parts, which are adjacently located with the plate-like portion being interposed therebetween, include inflow ports allowing the inflation gas to flow thereinto which are located above the plate-like portion.
In the specification, the terms xe2x80x9cthe longitudinal directionxe2x80x9d and xe2x80x9cthe vertical directionxe2x80x9d mean respectively the xe2x80x9cfront and back directionxe2x80x9d and the xe2x80x9cupward and downward directionxe2x80x9d of the vehicle with the head protection airbag device installed thereto.
In the first head protection air bag device, when inflation gas is made to flow into the air bag and the developing and inflating operation of the air bag is completed, the inflation parts partitioned by the partitioning parts in each inflatable protective shielding part generate a tension having a longitudinal direction in the inflatable protective shielding part per se. The inflatable protective shielding parts are interconnected by the inflation communicating parts in the lower fringe side of the air bag.
The inflation communicating parts are longitudinally disposed along the lower fringe of the air bag, and completes the inflation of the air bag. Therefore, the inflatable protective shielding parts are interconnected without reducing the tensions in those parts. As a result, a high tension having the longitudinal direction is generated in the entire lower fringe of the air bag.
The inflation parts are interconnected such that only those inflation parts adjacent to each other are merely interconnected by the inflation communicating part. The remaining inflation parts are closed at the lower edges of the periphery parts. Accordingly, even if the inflation communicating parts are provided, the tension having a longitudinal direction in the inflatable protective shielding part per se, which is generated by the inflation parts, is kept in a high level.
Accordingly, the head protection air bag device of the invention is capable of generating a high tension having the longitudinal direction of the vehicle in the lower fringe side of the air bag at the completion of developing and inflating the air bag.
Particularly in the lower side of the plate-like portion in the air bag, the inflation communicating part completes the inflating operation in a state that high tension having the longitudinal direction is generated in the lower edge side of the air bag. Accordingly, the air bag is high in rigidity, and difficult to be bent to the outside of the car cabin. Therefore, even if the passenger is greatly moved out of the car cabin and pressed against the lower end in the vicinity of the lower end of the plate-like portion, the passenger can be restrained reliably.
If attempt is made to obtain high tension by locating anew an inflation part at the position of the plate-like portion in the air bag of the invention, which the tension is high as high as in the air bag of the invention, if a strong pressing force acts the lower edge of the inflation part located anew in a cabin-outside direction, the inflation parts are specially firmly coupled to each other at their lower ends, the lower end of the newly installed inflation part is inevitably bent to the cabin-outside. Accordingly, the operation and effect of the invention cannot be obtained.
If the inflation part is located at the position of the plate-like portion in the air bag of the invention, the volume of the gas-inflow section increases, so that the time from the inflation start till inflating operation ends is increased. On the other hand, in the air bag of the invention, the plate-like portion in the non gas-inflow section which rejects the inflow of inflation gas is disposed above the inflation communicating parts. The volume of the gas-inflow section is small when comparing with the case where the inflation part is located at the position of the plate-like portion. Accordingly, the time from the inflation start till inflating operation ends is reduced.
Further, in the case that the coupling parts longitudinally extending away from the gas-inflow section and coupled to a body of the vehicle are coupled to the lower-edge side part of the periphery parts, much higher tension of a longitudinal direction of the vehicle may be generated in the lower fringe side of the air bag at the completion of developing and inflating operations of the air bag.
Still further, in the case that the inflatable protective shielding parts, which are adjacently located with the plate-like portion being interposed therebetween, receive the inflation gas through the inflow ports located above the plate-like portion, a flowing distance of the inflation gas till it reaches the front inflatable protective shielding part, which was set to be long, is shorter than that in the air bag in which the inflation gas is fed into air bag from one of the ends of the gas-inflow section. Accordingly, the time taken from the inflation start of the whole gas-inflow section till inflating operation ends is reduced.
Further, there is provided a second head protection air bag device having an air bag which is stored, while being folded, along the upper fringe of an opening on the cabin-inside or indoor side and on the side of seat recliners, and when receiving inflation gas, the air bag develops and inflates to cover the opening,
wherein the air bag includes a gas-inflow section through which the inflation gas is introduced into the air bag, and a periphery part surrounding the gas-inflow section,
the gas-inflow section is partitioned, by partitioning/coupling parts coupling the cabin-inside side wall with the cabin-outside side wall, into a plurality of inflation parts, which are arranged side by side in the longitudinal direction, and inflate when receiving the inflation gas so as to separate the cabin-inside side wall and the cabin-outside side wall one from the other, and
the inflation parts located on the side of the seat recliners serve as lower-end displacement inflation parts located such that the lower ends thereof are higher than the lower ends of the other inflation parts, thereby preventing it from interfering with the upper ends of the seat recliners.
In the second head protection air bag device, it is preferable that parts of the periphery part, which are located under the lower-end displacement inflation parts of the air bag, are substantially level with parts of the periphery parts under the inflation parts, which are adjacent to the lower-end displacement inflation parts, in the lower edge height, when the air bag is developed to be flat in a non inflating state.
In the head protection air bag device, it is preferable that the gas-inflow section includes a front-seat inflow section and a rear-seat inflow section, which are respectively provided covering openings on the side of the front seat and rear seat,
the front-seat inflow section and the rear-seat inflow section include, respectively, lower-end displacement inflation parts corresponding to the front seat and the rear seat, and
a width dimension of the lower-end displacement inflation part of the front-seat inflow section as longitudinally viewed is larger than that of the lower-end displacement inflation part of the rear-inflow section as longitudinally viewed.
In the second head protection air bag device, it is preferable that the air bag introduces the inflation gas thereinto both at the time of side collision and at the time of the roll-over.
In the second head protection air bag device according to the present invention, the lower-end displacement inflation parts are disposed such that the lower ends of them are located at positions above the lower ends of the remaining inflation parts, when the folded air bag receives the inflation gas, and its developing/inflating operation is completed. With this feature, the air bag inflates without any interference with the upper ends of the seat recliners. The remaining inflation parts are disposed such that the lower ends of them are located at positions lower than the upper ends of the seat recliners. Accordingly, those may be developed and inflated so as to broadly cover the openings on the cabin-inside side. The developing/inflating operation of the entire air bag may be completed without any hindrance.
Accordingly, in the head protection air bag device according to the invention, even in such a construction that the air bag broadly covers the openings on the cabin-inside side, the air bag may be developed and inflated without any interference of the seat recliners.
Further, even if the lower-end displacement inflation parts are disposed such that the lower ends of them are located at positions above the lower ends of the remaining inflation parts when the developing/inflating operation of the air bag is completed, in the case that the parts of the lower-edge side part under the lower-end displacement inflation parts interfere with the upper ends of the seat recliners and are disposed, while being bent, so that their lower edge side are made to be coincident, as much as possible, with the parts of the lower-edge side part of the periphery parts at the lower side of the adjacent inflation parts, the head protection air bag device is capable of generating the tension having the longitudinal direction in the lower edge side of the air bag. When the developing/inflating operation is completed, the sideways movement of the air bag is restricted and the passenger is reliably restrained even if a pressing force acts the air bag in a cabin-inside or a cabin-outside direction.
Still further, in the case that an adjustable range of a front seat in the longitudinal direction is longer than of a rear seat, and that even when the front seat is adjusted over a long range in the longitudinal direction and the width dimension (as longitudinally viewed) of the lower-end displacement inflation part of the front-seat inflow part is larger than that of the lower-end displacement inflation part of the rear-seat inflow part, when the lower-end displacement inflation part of the front-seat inflow part is developed and inflated, the lower end of the lower-end displacement inflation part is prevented from interfering with the upper end of the seat recliner of the adjusted front seat. As a result, the third head protection air bag device is smoothly operable even when it is mounted on the vehicle provided with the front and rear seats.
Still further, in the case that the both at the time of side collision and at the time of the roll-over, the air bag is developed and inflated to broadly cover the openings on the cabin-inside side, the air bag reliably protects the passenger at the time of over rolling as well as at the time of the side-collision of the vehicle.
Features and advantages of the invention will be evident from the following detailed description of the preferred embodiments described in conjunction with the attached drawings.